Trends and periodicities in observed temperature,precipitation and runoff in a desert catchment: case study for the Shiyang River Basin in Northwestern China

The Mann–Kendall test, wavelet analysis was used to analyse the long‐term trends and periodicities in temperature, precipitation and streamflow in China's Shiyang River Basin since 1950. The Principal components analysis (PCA) was used to quantify the impacts of climate change and human activities on water resources. The annual mean air temperature has increased, consistent with increasing global temperatures. The annual precipitation fluctuated but has generally increased since the 1990s. The air temperature and precipitation showed changes on periods ranging from 2 to 28 years. The correlation between annual runoff and precipitation variation was 0.61 (P < 0.05), indicating precipitation is the main source of the runoff. Human activities played the dominant role in the lower reaches, accounting for 58.5% of the total effect. The results have important implications for water resources management to support harmonisation of the relationship between humans and nature to combat the effect of climate.     

Motivation,commitment and the use of incentives in partnerships and alliances

The use of incentives in partnering and alliancing has been seen as an important way of reinforcing collaboration in the short term and helping to build trust between clients and contractors in the long term. Yet only rarely has the impact of incentives on such relationships been discussed, let alone subjected to systematic investigation. This is despite a wealth of theory and research which brings into question the use of incentives and reinforcers as ways of generating motivation and commitment. Drawing upon this theoretical knowledge base and using evidence from a number of case studies of partnerships and alliances, this paper demonstrates how a number of important cognitive and social dimensions affect the use and impact of incentives, sometimes in ways contrary to those intended. The conclusion drawn is that there are important limitations to the use of incentives as means of reinforcing collaboration and developing commitment and trust, and that this raises questions more generally about the assumptions that underlie many of the practical ‘tools and techniques’ commonly associated with partnering and alliancing.     

Tunnel vision? Brunel's Thames Tunnel and project narratives

Looking at historical projects has much to offer our understanding of project management, for both research and practice. However, there are important challenges in how alternative narratives about such projects are reconstructed and related to each other. To explore these challenges, this paper uses the example of the Thames Tunnel project, completed under the direction of Marc Brunel in 1843, and reputed to be the first tunnel to be built under a major river. In telling the story of the project, we focus on five alternative discourses: technico-rational; practice; networks of people, things, and ideas; politics; and society. The common response to such variety is either to attempt to construct an overarching meta-narrative, or to explore the differences as a way of highlighting the localized and contingent nature of knowledge about projects, or adopt some intermediate position somewhere on the spectrum between these two extremes. Instead we seek a different route grounded in a sociology of knowledge that acknowledges simultaneous, provisional, and contested processes of division and stabilization in the ways that epistemic communities constitute knowledge through their own narratives and practices. These have implications for the stories that are told about project management and, crucially, the activities and interests that both shape and are shaped by such narratives.     

Crystallographic Structure and Ferroelectricity of (AxLa1−x)2Ti2O7 (A = Sm and Eu) Solid Solutions with High Tc

The solubility and ferroelectric properties of (A_xLa_1?x)₂Ti₂O₇ (A = Sm and Eu) solid solutions were investigated. The crystallographic structure of the solid solutions was studied using X‐ray diffraction and Raman spectroscopy. The solubility limits of Eu and Sm in (A_xLa_1?x) ₂Ti₂O₇ were found to be greater than x = 0.5 and 0.8, respectively. The solid solutions had a monoclinic perovskite‐like layered structure (PLS), similar to that of the pure La₂Ti₂O₇, when x was less than the solubility limit. When x was above the solubility limit the materials were biphase. The biphases of (Sm_xLa_1?x)Ti₂O₇ (x = 0.9) consisted of (Sm_xLa_1?x)₂Ti₂O₇ with PLS and pure Sm₂Ti₂O₇ with pyrochlore structure, and the biphases of (Eu_xLa_1?x)Ti₂O₇ (x = 0.6, 0.7, and 0.8) consisted of (Eu_xLa_1?x)₂Ti₂O₇ with PLS structure and La³⁺ doped Eu₂Ti₂O₇ with pyrochlore structure. The effect of A‐site substitution on the properties of La₂Ti₂O₇ was investigated by measuring the dielectric permittivity and loss at different frequencies and temperatures. The highest piezoelectric constant d₃₃ was 2.8 pC/N for (Sm_0.1La_0.9)Ti₂O₇.     

New breathable films using a thermoplastic cross‐linked starch as a porogen

Breathable films, which find in variety of product applications, are conventionally made using mineral porogens such as calcium carbonate (CaCO₃). This article addresses a novel biodegradable and highly breathable film without inorganic porogens. Unexpectedly, a thermoplastic cross‐linked natural polymer (corn starch) was used successfully to create tortuous passages for film breathability. This concept was demonstrated using two types of thermoplastic cross‐linked corn starches as porogens and contrasted to control samples: native corn and chemically cross‐linked starches, respectively. The films discussed had increased breathability and mechanical properties relative to the control samples. The film morphology reveals that filler was irregular when thermoplastic starch or CaCO₃ was used. The difference in filler from chemically modified cross‐linked starch and thermoplastic cross‐linked starch was observable as well. It is believed that spherical particles provided by thermoplastic cross‐linked starch helps film debonding and porosity during the film stretch processes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41016.     

在LTspice/SwitcherCAD Ⅲ中采用变压器

关于LTspice/SwitcherCAD Ⅲ LTspice/SwitcherCAD Ⅲ是一款具集成原理图捕获能力的强大SPICE仿真工具.     

iFlash:80℃活化漂白与新型皂洗

加工技术与设备的发展通常会使加工时间缩短.但是新型助剂的应用也可减少加工时间,大大降低成本.随着iFlash系统的应用,漂白温度可降至80℃,活性染料染色后皂洗的时间也大大缩短.因此,织物间歇式染色得到优化,在不增加额外投资的情况下运行更经济.     

Polynomial methods for the structured singular value with real parameters

We consider the structured singular value problem with real parametric uncertainty only. Using techniques from algebraic geometry, we propose two algorithms that in principle can yield the precise value of the structured singular value at a fixed frequency. Their ability to do so depends upon their ability to find all common roots to a system of polynomial equations. The first algorithm is applicable to problems with two real parameters each of multiplicity two. The second algorithm is applicable to problems with n distinct real parameters. These algorithms have proved useful in applications to aerospace control law analysis.     

The performance of a distributed combat simulation with the time warp operating system

This paper analyzes the performance of a discrete-event combat simulation executed on a parallel processor under control of the Time Warp Operating System. Time Warp is in a class of distributed simulation methods called Optimistic methods which have proven to be useful over a wide range of simulations. The combat simulation used for this performance study, called STB88, is a division-corps model incorporating a number of different types of computations. The speed-up for three versions of this model on the Caltech/JPL Mark III Hypercube and the BBN Butterfly parallel processors was measured relative to an efficient sequential execution of the same model on the same hardware. The results indicate that STB88 version 1 achieves a speed-up of 28.6 on 60 Mark III processors, while STB88 version 2 achieves a speed-up of 36.8 on 100 Butterfly processors. Version 3 of STB88 achieved a speed-up of 38.5 on 128 Mark III processors. The versions differed only in their interface to Time Warp. On the Butterfly, the sequential execution completed in 2 hours, while the 100 processor execution completed in 3.2 minutes.